Add Admin user/pass as arguments

Add Admin user/pass as arguments

- This Patch makes admin username and password as arguments
  with censor as true instead of challenging as input. This
  will print the string as wildcard in the command line as
  well as history file.

- eliminates the use of cache to avoid one session login to
  be used in another session.

- Deleted the aliases in the options with censor enabled due to the
  problem in karaf (https://issues.apache.org/jira/browse/KARAF-6769)

JIRA: AAA-189
Signed-off-by: gvrangan <vgovindarajan@luminanetworks.com>
Change-Id: Ief5b0177273baf39fc8afe248b8e5055f40cdc0e